Investigatory rhymes with:
derogatory, interrogatory, obligatory, purgatory, accusatory, aleatory, ambulatory, anticipatory, articulatory, celebratory, circulatory, compensatory, conciliatory, confirmatory, confiscatory, congratulatory, contributory, declaratory, defamatory, depilatory, depository, deregulatory, derogatory, dilatory, discriminatory, dormitory, excretory, exculpatory, expiratory, explanatory, exploratory, hallucinatory, incantatory, inflammatory, inhibitory, interrogatory, laboratory, laudatory, lavatory, mandatory, migratory, nondiscriminatory, obligatory, observatory, oratory, oscillatory, participatory, predatory, preparatory, prohibitory, purgatory, reformatory, regulatory, repository, respiratory, retaliatory, revelatory, signatory, statutory, transitory